Disorders of Consciousness: Somnolence, Sopor and Coma: Test and Diagnosis

Laboratory parameters of the 1st order – obligatory laboratory tests.

• Small blood count
• Inflammatory parameters – CRP (C-reactive protein).
• Urine status (rapid test for: pH, leukocytes, nitrite, protein, glucose, ketone, urobilinogen, bilirubin, blood).
• Electrolytes – sodium, potassium, chloride, calcium.
• Fasting glucose (fasting blood glucose).
• Blood gas analysis (ABG); determination of.
  • Venous: pH, BE, HCO3 -, (lactate) [lactate ↑ = oxygen deficiency due to inhibition of aerobic glycolysis].
• Serum ethanol concentration – in coma of unclear genesis/origin.
• Thyroid parameter – TSH
• Liver parameters – alanine aminotransferase (ALT, GPT), aspartate aminotransferase (AST, GOT), glutamate dehydrogenase (GLDH) and gamma-glutamyl transferase (gamma-GT, GGT), alkaline phosphatase, bilirubin.
• Renal parameters – urea, creatinine, cystatin C or creatinine clearance, if necessary.
• Coagulation parameters – INR/PTT, Quick
• Highly sensitive cardiac troponin T (hs-cTnT) or troponin I (hs-cTnI); creatine kinase (CK, CK-MB), lactate dehydrogenase (LDH) – in coma of unclear genesis or suspected myocardial infarction (heart attack).
• Blood cultures

Laboratory parameters 2nd order – depending on the results of the history, physical examination and obligatory laboratory parameters – for differential diagnostic clarification.

• CSF puncture (lumbar puncture/extraction of cerebrospinal fluid by puncture of the spinal canal) for CSF diagnosis – In all cases of coma of unclear etiology that has not been definitively assigned (this also applies if there is no meningismus (painful neck stiffness) and no systemic signs of inflammation and no subarachnoid blood is seen on CT skull (CCT)).
• Hormone diagnostics – cortisol, ACTH, etc.
• Toxicological tests (from reserve samples) – if intoxications are suspected.